Within the power generation industry, large-scale power generators convert mechanical energy, typically the energy output of a turbine, into electrical energy. Some of the basic components of such power generators may include a frame-supported stator core that provides a relatively high permeability path for enabling a magnetic field, and a rotor assembly positioned to rotate within the stator core, so as to induce electrical current through rotor-borne conductors moving through the magnetic field set up within the stator. The resulting current may be conducted to a power plant bus for eventual power distribution to consumers, commercial establishments, and any other users of electrical power.
According to well-understood physical principles of electrical conduction through a conductor, electric current flow occurs as a result of the flow of electrons that move under the influence of an electric field through the conductor. In practical devices, heat is generated as a result of electron-level collisions, raising the temperature of the conductor and the surrounding environment. This effect can be especially pronounced within large-scale power systems where large currents are generated. Conductor cooling is a conventional technique used in relatively large turbine-generator systems for dissipating heat to cooling media within their housing. A cooling medium that is often used in such turbine-generators is hydrogen. It is known to use shaft seal assemblies to prevent the hydrogen gas from escaping from the generator housing.
In a typical shaft seal assembly, sealing oil is pumped by way of an external power plant piping 10, as may be appreciated in FIG. 5, that feeds sealing oil to a passageway internally disposed in a bracket member 12. This inlet passageway in the bracket passes oil to a corresponding internal passageway in a sealing cartridge for delivery to the rotor surface for sealing purposes. The oil leaving both the air and hydrogen sides of the seal assembly is then typically collected and returned via corresponding internal outlet passageways in the sealing cartridge and the bracket connected to power plant piping 14, such as may be connected to return the oil to a seal oil reservoir (not shown).
The foregoing presumes that one is able to readily and consistently align the internal passageways to one another. In practice, the position, e.g., radial position, of any given power plant piping, such as either oil supply pipe 10 or oil return pipe 14, relative to the inlet passageway or outlet passageway in the bracket may vary from plant to plant. For example, the point of arrival (or departure) of the power plant piping is not under the control of the manufacturer of the generator seal and could be at any quadrant on the frontal face of the bracket, e.g., left side, right side, top side, bottom side, etc. This poses interface challenges since plant-to-plant variation in the radial position of the external power plant piping may require ad hoc modification of components in the seal assembly in order to ensure an appropriate registration between the bracket passageways and the seal cartridge passageways. Accordingly, it would be desirable to address the foregoing interface challenges to provide, at a relatively low-cost, structural means and techniques that allow for reliable passage of sealing oil for the shaft seal assembly, without being affected due to variation that may occur in the location of the power plant piping.